After the upgrade of Mangustas to the CBT standard between 2001 and 2008, and operated during the Second Gulf War in Iraq and Afghanistan from 2004 to 2006, the Italian Army decided to upgrade the A-129CBT with new avionics, systems, and weapons. One of these weapons was the fire-and-forget SPIKE ER ATGM, guided by the Rafael TOP LITE optic at the start of the launch and during the subsequent tracking of the SPIKE missile. With this upgraded version of the A-129, it lost the ability to launch TOW missiles due to its new optic. The first AH-129D (Delta) were acquired in 2014 for the 5°Reggimento AVES (Aviazione dell'Esercito). In the same year, a total of 32 A-129CBT were upgraded to the Delta standard. The AH-129D was immediately deployed and remained in service in Afghanistan until 2021, when ISAF troops left the country. Nowadays, there are 32 AH-129D operational and 16 A-129CBT for training.

Introduced in Update "Kings of Battle", the main difference between the AH-129D and the A-129CBT is primarily armament. The Delta is able to equip SPIKE ERs but no TOWs, which are fire-and-forget missiles that track every type of target, simultaneously, thus giving the potential to knock out 8 targets in quick succession. However, the main problem with the SPIKE is its speed. The rest of the helicopter remains the same as the A-129CBT, with good manoeuvrability and acceleration, and a wide selection of air-to-ground and air-to-air armaments.